include/asm-ppc/dma-mapping.h

   1 /*
   2  * This is based on both include/asm-sh/dma-mapping.h and
   3  * include/asm-ppc/pci.h
   4  */
   5 #ifndef __ASM_PPC_DMA_MAPPING_H
   6 #define __ASM_PPC_DMA_MAPPING_H
   7
   8 #include <linux/config.h>
   9 /* need struct page definitions */
  10 #include <linux/mm.h>
  11 #include <asm/scatterlist.h>
  12 #include <asm/io.h>
  13
  14 #ifdef CONFIG_NOT_COHERENT_CACHE
  15 /*
  16  * DMA-consistent mapping functions for PowerPCs that don't support
  17  * cache snooping.  These allocate/free a region of uncached mapped
  18  * memory space for use with DMA devices.  Alternatively, you could
  19  * allocate the space "normally" and use the cache management functions
  20  * to ensure it is consistent.
  21  */
  22 extern void *__dma_alloc_coherent(size_t size, dma_addr_t *handle, gfp_t gfp);
  23 extern void __dma_free_coherent(size_t size, void *vaddr);
  24 extern void __dma_sync(void *vaddr, size_t size, int direction);
  25 extern void __dma_sync_page(struct page *page, unsigned long offset,
  26                                  size_t size, int direction);
  27 #define dma_cache_inv(_start,_size) \
  28         invalidate_dcache_range(_start, (_start + _size))
  29 #define dma_cache_wback(_start,_size) \
  30         clean_dcache_range(_start, (_start + _size))
  31 #define dma_cache_wback_inv(_start,_size) \
  32         flush_dcache_range(_start, (_start + _size))
  33
  34 #else /* ! CONFIG_NOT_COHERENT_CACHE */
  35 /*
  36  * Cache coherent cores.
  37  */
  38
  39 #define dma_cache_inv(_start,_size)             do { } while (0)
  40 #define dma_cache_wback(_start,_size)           do { } while (0)
  41 #define dma_cache_wback_inv(_start,_size)       do { } while (0)
  42
  43 #define __dma_alloc_coherent(gfp, size, handle) NULL
  44 #define __dma_free_coherent(size, addr)         do { } while (0)
  45 #define __dma_sync(addr, size, rw)              do { } while (0)
  46 #define __dma_sync_page(pg, off, sz, rw)        do { } while (0)
  47
  48 #endif /* ! CONFIG_NOT_COHERENT_CACHE */
  49
  50 #define dma_supported(dev, mask)        (1)
  51
  52 static inline int dma_set_mask(struct device *dev, u64 dma_mask)
  53 {
  54         if (!dev->dma_mask || !dma_supported(dev, mask))
  55                 return -EIO;
  56
  57         *dev->dma_mask = dma_mask;
  58
  59         return 0;
  60 }
  61
  62 static inline void *dma_alloc_coherent(struct device *dev, size_t size,
  63                                        dma_addr_t * dma_handle,
  64                                        gfp_t gfp)
  65 {
  66 #ifdef CONFIG_NOT_COHERENT_CACHE
  67         return __dma_alloc_coherent(size, dma_handle, gfp);
  68 #else
  69         void *ret;
  70         /* ignore region specifiers */
  71         gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
  72
  73         if (dev == NULL || dev->coherent_dma_mask < 0xffffffff)
  74                 gfp |= GFP_DMA;
  75
  76         ret = (void *)__get_free_pages(gfp, get_order(size));
  77
  78         if (ret != NULL) {
  79                 memset(ret, 0, size);
  80                 *dma_handle = virt_to_bus(ret);
  81         }
  82
  83         return ret;
  84 #endif
  85 }
  86
  87 static inline void
  88 dma_free_coherent(struct device *dev, size_t size, void *vaddr,
  89                   dma_addr_t dma_handle)
  90 {
  91 #ifdef CONFIG_NOT_COHERENT_CACHE
  92         __dma_free_coherent(size, vaddr);
  93 #else
  94         free_pages((unsigned long)vaddr, get_order(size));
  95 #endif
  96 }
  97
  98 static inline dma_addr_t
  99 dma_map_single(struct device *dev, void *ptr, size_t size,
 100                enum dma_data_direction direction)
 101 {
 102         BUG_ON(direction == DMA_NONE);
 103
 104         __dma_sync(ptr, size, direction);
 105
 106         return virt_to_bus(ptr);
 107 }
 108
 109 /* We do nothing. */
 110 #define dma_unmap_single(dev, addr, size, dir)  do { } while (0)
 111
 112 static inline dma_addr_t
 113 dma_map_page(struct device *dev, struct page *page,
 114              unsigned long offset, size_t size,
 115              enum dma_data_direction direction)
 116 {
 117         BUG_ON(direction == DMA_NONE);
 118
 119         __dma_sync_page(page, offset, size, direction);
 120
 121         return page_to_bus(page) + offset;
 122 }
 123
 124 /* We do nothing. */
 125 #define dma_unmap_page(dev, handle, size, dir)  do { } while (0)
 126
 127 static inline int
 128 dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
 129            enum dma_data_direction direction)
 130 {
 131         int i;
 132
 133         BUG_ON(direction == DMA_NONE);
 134
 135         for (i = 0; i < nents; i++, sg++) {
 136                 BUG_ON(!sg->page);
 137                 __dma_sync_page(sg->page, sg->offset, sg->length, direction);
 138                 sg->dma_address = page_to_bus(sg->page) + sg->offset;
 139         }
 140
 141         return nents;
 142 }
 143
 144 /* We don't do anything here. */
 145 #define dma_unmap_sg(dev, sg, nents, dir)       do { } while (0)
 146
 147 static inline void
 148 dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
 149                         size_t size,
 150                         enum dma_data_direction direction)
 151 {
 152         BUG_ON(direction == DMA_NONE);
 153
 154         __dma_sync(bus_to_virt(dma_handle), size, direction);
 155 }
 156
 157 static inline void
 158 dma_sync_single_for_device(struct device *dev, dma_addr_t dma_handle,
 159                         size_t size,
 160                         enum dma_data_direction direction)
 161 {
 162         BUG_ON(direction == DMA_NONE);
 163
 164         __dma_sync(bus_to_virt(dma_handle), size, direction);
 165 }
 166
 167 static inline void
 168 dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, int nents,
 169                     enum dma_data_direction direction)
 170 {
 171         int i;
 172
 173         BUG_ON(direction == DMA_NONE);
 174
 175         for (i = 0; i < nents; i++, sg++)
 176                 __dma_sync_page(sg->page, sg->offset, sg->length, direction);
 177 }
 178
 179 static inline void
 180 dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nents,
 181                     enum dma_data_direction direction)
 182 {
 183         int i;
 184
 185         BUG_ON(direction == DMA_NONE);
 186
 187         for (i = 0; i < nents; i++, sg++)
 188                 __dma_sync_page(sg->page, sg->offset, sg->length, direction);
 189 }
 190
 191 #define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
 192 #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
 193 #ifdef CONFIG_NOT_COHERENT_CACHE
 194 #define dma_is_consistent(d)    (0)
 195 #else
 196 #define dma_is_consistent(d)    (1)
 197 #endif
 198
 199 static inline int dma_get_cache_alignment(void)
 200 {
 201         /*
 202          * Each processor family will define its own L1_CACHE_SHIFT,
 203          * L1_CACHE_BYTES wraps to this, so this is always safe.
 204          */
 205         return L1_CACHE_BYTES;
 206 }
 207
 208 static inline void
 209 dma_sync_single_range_for_cpu(struct device *dev, dma_addr_t dma_handle,
 210                               unsigned long offset, size_t size,
 211                               enum dma_data_direction direction)
 212 {
 213         /* just sync everything for now */
 214         dma_sync_single_for_cpu(dev, dma_handle, offset + size, direction);
 215 }
 216
 217 static inline void
 218 dma_sync_single_range_for_device(struct device *dev, dma_addr_t dma_handle,
 219                                  unsigned long offset, size_t size,
 220                                  enum dma_data_direction direction)
 221 {
 222         /* just sync everything for now */
 223         dma_sync_single_for_device(dev, dma_handle, offset + size, direction);
 224 }
 225
 226 static inline void dma_cache_sync(void *vaddr, size_t size,
 227                                   enum dma_data_direction direction)
 228 {
 229         __dma_sync(vaddr, size, (int)direction);
 230 }
 231
 232 static inline int dma_mapping_error(dma_addr_t dma_addr)
 233 {
 234         return 0;
 235 }
 236
 237 #endif                          /* __ASM_PPC_DMA_MAPPING_H */